<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			.father{
				width: 1200px;
				height: 500px;
				background-color: rgba(255,0,0,0.3);
				margin: 0 auto;
				display: flex;
				flex-direction: row-reverse;
			}
			.father>div{
				border: 1px solid #000;
				height: 150px;
				text-align: center;
				line-height: 150px;
				flex: 1;
			}
			.father>div:nth-child(2){
				flex: 2;
			}
		</style>
	</head>
	<body>
		<div class="father">	
			<div>
				<div>1</div>
				<div>2</div>
				<div>3</div>
			</div>
			
		</div>
	</body>
</html>
